Method and apparatus for detecting defects in filled cans



May 21, 1946. R. o. HENSZEY EI'AL METHOD AND APPARATUS FOR DETECTING DEFECTS IN FILLED CANS Original Filed May 27, 19:59 8 sheets-sheet 1 QQ 3W MNN w B May 21, 1946. R. O.-HENSZEY ET AL METHOD AND APPARATUS FOR DETECTING DEFECTS IN FILLED CANS Original Filed May 27, 1939 8 Sheets-She'et 2 n In 55 INVENTORS O. fiwzg 6+ Mfm m Q4fm/M@ y 1946- R. o. HENSZEY ET AL 2,400,507

METHOD AND APPARATUS FOR DETECTING DEFECTS IN FILLED CANS Original Filed May 27, 1939 8 Sheets-Sheet 3 May 21, 1946. R. o. HENSZEY ETAL METHOD AND APPARATUS FOR DETECTING DEFECTS IN FILLED CANS 8 Sheets-Sheet 4 INVENTORSv Original Filed May 2'? 1939 May 21, 1946. R. o. HENSZEY ETAL METHOD AND APPARATUS FOR DETECTING DEFECTS IN FILLED CANS Original Filed May 27, 1939 8 Sheets-Sheet 5 INVENTORJ, .2?? a /%7Z6'Zy ad 6772.225 344 7; H Zzz W, M

y 1946. R. o. HENSZEY EI'AL 2,400,507

METHOD AND APPARATUS FOR DETECTING DEFECTS IN FILLED CANS Original Filed May 27, 1959 8 sheets'shee" 6 iii-r12 172 5 19.

May 21, 1946- R. o. HENSZEY ET AL 2,400,507

METHOD AND APPARATUS FGR EETECTING DEFECTS IN FILLED CANS Original Filed May 2'7, 1939 8 Sheets-Sheet '7 J56 0. flerzze 156 PM 622%;

: was 5 2%, ZI w #M w May 21, 1946. R, o. HENSZEY ET AL METHOD AND APPARATUS FOR DETECTING DEFECTS IN FILLED CANS Original Filed May 27, 1939 8 Sheets-Sheet 8 a Q; INVENTOR5,

ja erzdz Patented May 21, 1946 METHOD AND APPARATUS FOR DETECTING DEFECTS IN FILLED CANS Roy 0. Henszey and Paul Smart, Oconomowoc,

Wis., assignors to Carnation Company, Oconomowoc, Wis., a corporation of Delaware Original application May 27, 1939, Serlal No. 276,050. Divided and this application January 2, 1943, Serial No. 471,138

21 Claims.

The present invention relates to a method and apapretus for detecting defects in filled cans. More particularly, it relates to a method and apparatus for detecting filled cans which have abnormal internal pressures.

This application is a division of application Serial No. 27 6,050, filed May 27, 1939, now Patent No. 2,339,638, dated January 18, 1944.

It is an object of the present invention to provide a, method and apparatus for detecting filled containers having abnormal internal pressures.

Another object of the present invention is to provide a, method and apparatus for testing a succession of small, filled containers to determine the internal pressure of such containers.

Still another object is to provide a method and apparatus for testing a succession of small, filled containers to determine the internal pressure of such containers and for directing those containers having abnormal internal pressure along one path and those with normal internal pressures along another.

A still further object is to provide a method and apparatus for testing a succession of filled containers at high speed to determine their internal pressures and for rejecting those of abnormal internal pressures.

Still another object is to provide a method and apparatus for detecting the internal pressures of small, filled containers and for directing those of abnormal internal pressure along one path and those of normal internal pressures along another, which method and apparatus are particularly suited for use in conjunction with methods and apparatus for testing containers for other defects, whereby to test a succession of filled containers rapidly and accurately for a number of types of defects.

A further object of the invention is to provide a method or means for detecting filled cans in which the internal pressure is above or below normal, in which the apparatus is simple and inexpensive in construction and eflicient in operation and wherein there is provided means for sorting cans according to the contour thereof, preferably according to the contour of an end or ends thereof A still further object of the invention is to provide means for rendering a pressure testing mechanism operated in conjunction with other testing mechanism inoperative under predetermined circumstances whereby the pressure testing mech anism may be driven by means common to other testing means and may, nevertheless, be rendered inoperative without rendering such other testing means inoperative simultaneously.

Other and further objects and advantages of the invention will be apparent from the followmg description taken in connection with the accompanying drawings wherein Figure 1 is a view in elevation of a portion of the machine;

Figure 2 is a section taken substantially along the line 2-2 of Figure 1;

Figure 3 is a view in perspective of a, part of the can feeding track, including a portion for controlling the operation of the machine;

Figure 4 is a view in perspective of the machine controlling portion of the track;

Figure 5 is a fragmentary view in elevation of the track portion shown in Figure 3;

Figures 6 and 7 are views in section taken along the line S-B of Figure 5 for illustrating certain features of the operation of the mechanism shown in Figure 5;

Figure 8 is a, longitudinal section taken substantially along the line 88 of Figure 2;

Figure 9 is a fragmentary substantially vertical section taken along the line 99 of Figure 8;

Figure 10 is a fragmentary substantially vertical section taken along the line Ill-Ill of Figure 1;

Figure 11 is a. fragmentary longitudinal section through the contour testing mechanism which forms the subject of the present invention; the section being taken along the line ll-ll of Figure 2;

Figure 12 is an exploded view in perspective of the contour testing instrumentality;

Figure 13 is an enlarged view in perspective of a can guiding means forming part of the mechanism shown in Figure 11;

Figure 14 is a fragmentary, substantially vertical section through the contour testing instrumentality taken along the line M in Figure 1;

Figure 15 is a. fragmentary view in perspective of a portion of -the mechanism shown in Figure 14;

Figure 16 1s a fragmentary substantially vertical section taken along the line lG-IB of Figure 17;

Figure 17 is a fragmentary View in elevation from the left hand side of the mechanism shown in Figure 14;

Figure 18 is a view in elevation of a portion of the mechanism shown in Figure 17 showing certain elements thereof in a different position of operation;

Figure 19 is a view in section taken along the line lQ-IB ofFigure l7;

Figure is a view in section taken along the line 20-20 of Figure 17;

Figures 21 and 22 are views in perspective of certain switch operating members forming parts of the mechanism shown in Figures 11 and 20;

Figures 23 and 24 are sections taken along the lines 23-23 and 24-24 of Figure 25, illustrating the Operation of the contour measuring means;

Figure 25 is an enlarged substantially vertical section taken along the line 25--25 of Figure 11 with certain parts omitted for purposes of clarity in illustration;

Figures 26 and 27 are views of a portion of Figure 25 but with the parts in diiferent positions of operation;

Figure 28 is a fragmentary view in elevation of the can directing and rejecting means controlled by the contour measuring mechanism of Figures 11 to 27;

Figure 29 is a view in substantially vertical section taken along the line 29-48 of Figure 2B;

The various testing mechanisms are preferably arranged in association with the pressure testing mechanism in the order or sequence shown in Figure 1 for a number of reasons, chiefly as follows. The size testing mechanism 6, which eliminates mashed cans or cans which are longer than normal, is preferably placed first because no type of defect which would be discovered by e quent testing mechanisms would interfere with the proper operation of this size testing mechanism, and because long or mashed cans would jam or impair the accuracy of the pressure testing mechanism 8, the viscosity or fluid friction mechanism l2, and the weight testing mechanism It. The cans are next tested by the pressure testing mechanism 8 to detect and control the rejection of bloated cans in which the pressure is above normal and also cans in which the pressure is below normal. This test preferably follows the elimination of long or mashed cans because the presence of such cans in the pressure testing mechanism would interfere with its operation or impair its accuracy, and finger work may be done if only cans of the proper length are fed to the station for the testing of the pressure thereof. It is necessary in order to obtain smooth operation of the pressure testing mechanism that it operate only when cans are available for testing, and since the structure of the size testing mechanism is such as to make it convenient and economical to associate the control mechanism I with the inlet to the size testing mechanism, the pressure testing mechanism preferably follows immediately after the size testing mechanism. The cans passing the size and pressure tests are then tested for viscosity, and this test Preferably follows the other tests, for the accuracy of the viscosity test is improved by eliminating prior thereto all over-size cans and cans of abnormal pressure, and also because long or mashed cans and bloated cans would tend to jam in the viscosity testing mechanism. It is also essential for the proper operation of the viscosity testing mechanism that the cans to be tested be delivered to the testing mechanism in spaced succession and since, as will later appear, the pressure testing mechanism discharges the tested cans in spaced succession, the viscosity testing mechanism conveniently follows this pressure testing mechanism.

Light weight testin mechanism preferably follows the other testing mechanisms, because the prior elimination of cans which are defective as to size, and pressure makes it possible to utilize a.

more sensitive weight testing mechanism than could otherwise be satisfactorily employed and because it has been found most convenient and economical for the feeding and discharge of cans to use the weight testing mechanism by the inspection table.

The inspection table is preferably placed last because in this position it provides means for facilitating a checking of the operation of the machine and because the prior elimination of the cans which are abnormal in size, pressure, viscosity or weight renders any defects, such as dirty or rusty cans orcans defective in some other unusual way, more conspicuous.

Control mechanism responsive to the presence or absence of cans to be tested This control mechanism 4, as best shown in Figs. 3 to 9, is preferably supported or carried by a pair of spaced upright frame members 38 welded or otherwise secured at their ends to the horizontally spaced inclined main frame members 0, the upright frame members 38 held in spaced relation by reinforcing angle members or bars 42. Inclined can supporting and guiding tracks 44 of substantially L-shape in cross section at their outer ends are fastened to the inner surfaces of the upright frame members 38, the upstanding flanges of these L-shaped track members being spaced apart a distance somewhat greater than the ax al length of the usual cans so as to permit long, mashed or bloated cans to pass therealong with no jamming. The tracks 44 at their outer ends support a box-like frame 46 into which extends the lower end of the gravity feed means 36, and extending between the upper transverse portion of this frame 46 and the upper spacing bar 42 are a pair of spaced rails 48 spaced from the inwardly directed flanges of the tracks 44 a distance somewhat greater than the diameter of the cans 24, and acting to insure proper positioning and rolling of the cans along the tracks 44 and preventing the cans from jumping this track or the balanced track 50.

The balanced track 50 comprises a pair of spaced rails 52 having beveled edges 54 at one end and secured at their opposite ends to the spaced arms 55 of a mounting bracket 58 having an integral apertured boss Bil extending between the spaced arms 56 and secured to a shaft or rod 62 journaled at its opposite ends in the upright frame members 38 and held against axial movement by collars B4. The rails 52 are spaced apart, as shown in Fig. 6, a distance slightly less than the axial length of the can 24 between the top and bottom rims 66 and, as shown in Fig. 7, a distance greater than the diameter of the can and the diameter of the top and bottom rims 66 so that a can having its axis extending horizontally may r011 along the rails 52, but an endwise can having its axis extending vertically will drop between the rails 52. Inclined angle bars 68 are secured at their upper ends to the uprights 38 or to the track members 44 and extend below the rails 52 to receive therefrom the endwise cans and direct the same to a point of discharge or a receptacle from which the cans may be taken and placed on the plate 26. The inwardly directed bottom flanges of the tracks 44 are cut away to receive the outer end portions of the rails 52 of the balanced track, these rails lying inwardly of the plane of the upstanding flanges of the tracks 44, with the upper edges of the rails lying in the plane and constiuting extensions of the inwardly directed flanges of these tracks so that the cans will roll smoothly 2,coo,sov

under the action of gravity from the tracks ll onto and along the rails 52 to the size testing mechanism 6. The balanced track 50 includes means for urging the rails 52 in an upward direction, and this meanscomprises a coil spring 10 interposed between the lower surface of the bracket 58 and an adjustable nut 12 on a screw H secured to the lower spacing bar 42, as by the head of the screw and a locking nut 18. The screw 14 also provides adjustable stop means for engaging the bracket 58 to limit the downward deflection of the balanced track rails 52. The rails 52 of the balanced track 50 are pushed upward by the spring Ill and held downward by the weight of the cans. When the balanced track is about half full of cans it is pushed downward by the weight thereof to its normal position, in which position it acts through an adjustable screw 18 carried by a laterally projecting lug 80 on the bracket 58 to hold a circuit maker and breaker 82 of the micro switch type in open circuit position.

Themicro switch 82 is moved by the resiliency of its contact and by an auxiliary spring into a circuit closing position when the balanced track under the action of the spring 10 moves upwardly, the track being less than half full of cans. The micro switch 82 controls, in a manner later to be described, the operation 01 the pressure testing mechanism 8 to render the same inoperative when there is an insuliicient numberof cans available to warrant testing thereof, and to render-it operative when a sufficient number oi cans are available for testing and are positioned on the balanced track 50.

Size testing mechanism Mashed cans usually have some portion of one end bulged or bent outward, thus increasing the over-all can length. The size testing mechanism standing brackets 92 welded, or otherwise fas-- tened, at their lower ends to the longitudinal main frame members It. Each disk 84 has an outwardly flaring annular portion 84 which ex-' tends inwardly from the periphery of the disk,

and the remaining portion 98 of the inner surface of each disk constitutes a plane surfacesub stantially parallel to the like plane surface of the other dislc The plane surfaces 98 of the disks are spaced apart sui'liciently to permit a can of normal over-all length to pass therebetween, but cans which are of greater over-all length will be engaged by the annular outwardly flaring portions 94 of the disks and will be carried upwardly with the disks as they rotate about the axis of the shaft 88 and deposited onan inclined track 98 which is provided with can supporting bottom rails I which project into the space between'the disks 8 4, and side rails I02 which retain the cans on the rails I00 after they have rolled out of the disks 84. The track 98' may be supported on the longitudinal main frame members 40 many convenient and desired man- 86 secured to a shaft 88 jour ner, as, for example, by the spaced upright frame members llll. If desired. the track 98 may be used to convey the cans abnormal in size to a.

suitable receptacle, or the track may itself be used as a temporary storage place. when so used, the track preferably extends throughout the length ofthe machine, as shown in Fig. l to provide a maximum of such space.

The rails of the balanced track extend into a space between the diskg ll, with their upper edges lying above the parallel plane which passes through the axis of the shaft 8!, and these rails iz'terminate at their inner bevele edges 54 within the plane surfaces 96 of the dis 84 and adjacent to the outer end of laterally spaced rails I05. The rails I06 extend forwardly in the same plane aslthe rails 52 and carry the cans of normal size from the size testing mechanism 8 to the pressure testing mechanism 8.

The rails I06 form parts of a can supporting and feed track which, between the size testing mechanism 8 and the pressure testing mechanism 8, is provided with side bars I08 for main taining the'cans in proper position on the rails I06. The side bars 108. as well as the rails I06, may be secured to the upstanding frame members [M lying between the size testing mechanism and the pressure testing mechanism. The disks. ll of the size testing mechanism may be continuously driven by means of a V belt III] and a pulley H2 secured to one end of the shaft Bl.

Pressure testing mechanism The portion of the machine shown in the drawings including thepressure testing mechanism, the associated can directing and rejecting means, and the means controlling the operation of the pressure testing mechanism is the part of the machine'whlch forms the subject of the present invention. As pointed out above this application ls'a division of a copending application Beends. Therefore, filled cans in which the contents is at an abnormal pressure may be detected by a testing of the contour of an end or ends of the can. Mashed cans also may have one or both of their ends bowed inwardly or outwardly, and. hence, such mashed cans as pass through the size testing mechanism 6 may be detected as well asthe cans of abnormal pressure by means testing the contour of an end or ends of such cans.

The pressure testing mechanism 8 accordingly Provides means for testing the end contour of the cans and means for controlling can directing or rejecting means l0, whereby to reject filled cans of abnormal internal pressure and cans dei'ective in other particulars, as evidenced b their abnormal end contour.

The means for testing the contour of the end or ends of the can preferably comprises in the illustrative embodiment (Figs. 1 and 11 to 27) a star" wheel H4 providing a plurality of angularly spaced pockets H6 for successively receiving the cans to be tested from the rails I06, and for conveying the cans in succession between apaced end contour measuring and controlling devices H6 and I and onto the can directin or reiecting means I0.

The wheel II4 preferably comprises a central hub portion I22, Fig. 14, and axially spaced, radially projecting arms I24 in which are provided the pockets M6, the pockets ,I I6 being so formed as to provide a concave surface I26, Fig. 11, engaging a substantial portion of the periphery of the can. and an outer convex portion I26 merging with the concave portion whereby to facilitate the rolling of the cans into the pockets for testing thereof and out of the pockets after they have been tested. The "star wheel is secured at its central hub portion I22 to a shaft I60 journaled in bearing blocks I32 carried by the spaced upstanding arms I34 of a bracket I36 secured at its lower end to the longitudinal main frame member or members 40. The shaft I is driven by the V belt IIO through the intermediacy of a pulley I36 and a clutch mechanism I40 subsequently to be described.

Cans are retained within the star wheel during their movement between the contour testing devices H6 and I20 by means of guide bars I42, Figs. 11 and 13, having semi-circular portions I44 overlying the path of movement of the cans between these testing devices, the guide bars I42 being secured at one end to a plate I46 extending laterally from an upright frame member I04. The guide bars I42 are secured intermediately by angle bracket I46 to spaced plates I50, the plates I50 being secured to the arms I64 and I66 of the bracket which supports the shaft I30, and being provided with openings through which said shaft passes, as seen in Fig. 14. A leaf spring I52. extending between and parallel to the guide bars I42, is secured to said bar a by the cross strap I54, Fig. 13, and extends in a position to overlie and frictionally contact a can during the testing of its end contour so as to prevent the can from shifting in its pocket II6 during this testingooperation.

The end contour testing device II6 preferably comprises a plurality of vertically spaced bars or straps I56, I50, I60, each clamped at one end to and between spaced plates I62 which may be secured to the side bars I06 or formed integrally therewith, the bars I56, I56, I being fastened to the plates I62 in any convenient manner, as,

for example, by rivets, bolts or the like I64. The

uppeaand lower-bars I56 and I60 are joined by an electrically conducting strap I66 and electrically insulating straps I66 and I16. The Plates I62 to which the bars I56 and I60 are fastened by the bolts I64 are preferably of, electrical insulating material, although if they be of metal, the bars I56 and I60 and the bolts I64 may be insulated from such metal plates. Electric connection is made to the bars I56 and I60 through one of the bolts I64 associated therewith, and both bars are maintained at the same electrical tension by means of the electrically conducting, inter-connecting strap I66.

The strap I66 carries a generally U-shaped metallic frame I12, the cross piece of the frame carrying an adjustable electric contact I14 in allnement with a like adjustable electric contact I16 carried by the strap I66.

The bar I56 terminates at its free end inwardly of the straps I66, I 66, I10, and carries at its outer end an L-shaped piece or portion I16 having a forwardly projecting arm I66 forming an electric contact extending between the contacts I14 and I16 and adapted, upon flexure of the bar I66 relatlve to the bars I66 and I60, to engage one or the other of these contacts I16 and I14. The bar I66 is secured similarly to the bars I56 and I60. as previously described, between the insulating plates I62 although, if these plates be of metal. the bar and its clamping bolt I64 may be insulated therefrom. The electrical connection is made to the bar I56 through its clamping bolt I64.

The bars I56, I58 and I60 are provided with similar can feelers I62, I64, I66, the feelers I02 and I66 being secured to the bars I56 and I60 between the insulating straps I66 and I10 and insulating pieces or blocks I68. The feeler I64 is secured at its opposite ends to the bar I56 by pairs of insulating blocks I60 and I92. Each of the feelers I62, I64 and I66 is provided with a can I engaging cam surface I64 extending into the path of movement of an end edge of the can and at an angle to such path of movement so as to engage and be moved outwardly by the end of the can, as shown in Figs. 23 and 24, thereby flexing the bars I56, I56 and I60, the feelers I62, I64 and I66 projecting through openings I66, I66 and 200 in the adjacent plate I50. The bars I56, I56 and I60 are so spaced in relation to each other and in relation to a can in a pocket II6 of the starl' wheel II4 that the feelers I62 and I66 ride on the rim of the can, while the feeler I64 rides on some flat portion of the can near the center of the can end. The contacts I 14 and I16 are so adjusted in relation to the contact I60 that there is no electrical contact on normal cans, but a can in which the end is bowed or outwardly bent beyond a limit of tolerance, which may be a. few thousandths of an inch, will flex the bar I56 a greater or lesser amount relative to the bars I56 and I60, and contact I60 will thereupon engage either the contact I14 or the contact I16, depending upon whether the end of the can is bowed outwardly or inwardly.

The end contour testing device I20 for the other ends of the cans is similar in substantially all respects to the and contour testing device H6, and comprises resilient bars or straps 202, 204 and 200 each mounted at one end between. a pair of insulating plates 206 by means of bolts 2I0 through which electrical connection may be made to one of the outer bars and to the central bar. The outer bars are joined at their free ends by a conducting strap 2I2 and electrically insulating straps H4 and 2I6. The bars are provided with can engaging feelers 2I6. 220 and 222, similar to the feelers I62, I64 and I66, and similarly mounted on their respective bars. The strap 2I2 carries a metal frame 224 similar to the frame I12 and provided with an adjustable contact 226 alined with an adiustable contact 226 carried by the strap 2I2. The bar 204 terminates inwardly of the strap 2 I2 and carries an L-shaped piece or portion 260 providing a forwardly projecting electrical contact 262 extending between the contacts 226 and 226, and is similar inall'respects to the contact I60. The feelers 2I6 and 222, like the feelers I62 and I66, ride on the rim of the can but at the opposite end thereof, while the feeler 220 carried by the central bar 204-rides near the can center on some flat portion of the can end. It will be noted that the central bar I56 of the end contour testing device II6 lies substantially centrally between the bars I56 and I60, while the central bar 204 of the contour testing device I20 lies nearer the lower bar 206 than the upper bar 202. The reason for this difference in spacing is that the two ends of a can are of different shape, and therefore it is necessary to so place the bars that their feelers I84 and 220 will at the samc instant ride on flat portions of the cap, which flat portions are differently located on the two ends,

Since the end rims of the cans are not rectanular but circular, and since the ends of the cans are not plane surfaces but comprise concentric annulanrelativcly raised and recessed portions, means must be provided for energizing the contacts controlled by the feelers for only a short time and preferably while the outer feelers of each set engage the rim of the can at opposite ends of a diameter thereof and when the central [eeler of each set engages some fiat portion of a normal can end. This is accomplished by a timing and control device or means 234, Figs. 14 to 22, which comprises a drum-like member 236 keyed to one end of the shaft I30, provided in its rim 238 with a plurality of pairs of radially alined openings 240 and 242 slidably receiving radially shiftable pin 244. All of the pins 244 he in the same plane perpendicular to the axis of the shaft lilllv The pins of one pair are connected by a co-planar extension 246, which may integrally join the two pins in this pair: The other two pairs of pins are connected together by right and left generally U-shaped yoke members 248 encompassing the connection extension 246 for the first pair of pins. Each pair of pins is adapted to assume three positions: First. a neutral position in which both pins of the pair project equally beyond the periphery of the rim 238 of the drum: second, a first active position in which one pin of the pair lies flush with the periphery of the rim 238 while the other pin of the pair pro- .iects a greater than normal distance beyond the periphery of the drum; and, third, a second active position in which the end of the last mentioned pin of the pair lies substantially flush with the rim 238 while the other pin projects beyond the rim a greater than normal distance, Means are provided for retaining each pair oi pin in each of these three positions.

This means comprises a spring urged ball or roller 250 mounted with its spring 252 in an axially extendin opening in the rim 238 and adapted to engage in any one of the three spaced annular grooves 254 for one pin 244 of each pair of pics. The spring and ball are retained in their opening by a cover plate 255 fastened to the inner face of the drum. The pins 244 successively actuate a micro switch 258 through a lever 260 and an adjustable set screw 262 carried at the free end of the lever and adapted, upon operation of the lever 260, to engage and press the switch operating leaf spring 264. The lever 260 is pivoted to a pin or stud 2B6 carried by a mounting plate or bracket 26B. and the lever carries intermediate its ends a. cam lug 210 adapted upon rotation of the drum 236 to be engaged successively by the ins 244. thereby depressing the switch operating lever to actuate the switch 258 to a circuit closing position. The drum 236 is positioned on the shaft 130 in such angular relation to the "star wheel H4 that a pin 244 will engag and operate the switch lever 260 at a predetermined instant when a can in one of the pockets H6 of the "star" wheel is engaged by the outer feelers of the end contour testing devices H8 and I20 on opposite ends of a diameter of the can and when the central feeler of each device is. in the case of a normal can. engaged with the fiat p rtion of the end surface of the can. The switch 258 at this instant completes a circuit throu h the central bars of the devices H and I20 from the contacts I and 232 (or from the sets of contacts fi l-I16 and 226-228) to a pin actuating and controlling solenoid or means 212, the actuated core of which is provided with an enlarged head portion or member 214 normally underlying the path of movement of the pins 244 but adapted, upon actuation thereof, to enga e and move an alined pair of pins thereabove radially with respectto the drum to project the upper pin of the pair a greater than normal distance beyond the periphery of the rim 238. Therefore, if either set of feelers due to a can abnormality establish contact between the piece I10 or the piece 230 and one of their co-operating contacts when the switch 250 is closed, a circuit, subsequently to be described, will be closed to energize the solenoid 212 which in turn, and as above described, drives upward one of the pins 244 in the pinwheel or drum 238. This actuating pin is retained in its active position by the engagement of the sprin pressed ball with the innermost groove in the pin.

This actuated pin forms part of a means for controlling the can directing or rejecting means ID to effect the rejection of a can having an abnormal internal pressure, as evidenced by a can having an abnormal end contour, and also to elfect the rejection of cans which are defective for other reasons, and which such defects are evi danced by the abnormality of their and surfaces. This control means of which the actuated pin forms a part comprises a micro switch 216 mounted on a plate 218 bolted to one of the plates I50. the switch being provided with a resilient actuating strip or bar 280 adapted to be engaged by the arm 202 of a switch operating lever mechanism 284 pivoted on a stud 206 carried by the mountin plate 210. The arm 202 of the lever mechanism carries an adjustable set screw 288 for determining the amount of movement required of the lever mechanism to operate the switch 218. The other arm 290 of the lever mechanism 204 extends outwardly from the pivot stud 286 into the path of movement or an outwardly pre-set pin 244. as shown in Figs. 18 and 19, and this arm is further provided with an outer end portion 292 lying substantially in the plane of the pins 244 but formed as an arcuate portion concentric to the axis of the pinwheel or drum 236 and extending to a point, as shown in Fig. 17, closely adjacent the cam block or lug 210 carried by the switch arm 280. The outer movement of the lever mechanism 284 is limited by an adjustable stop 294 positioned to engage the lever arm 282, and is held in this position by a spring 296 extemiint between a first lug 208 of the mounting plate 210 and a lug 300 carried by lever am 290.

The micro switch 215 controls the operation of gate actuating solenoids 302 and 304, Fig. 29, which form part of the can directing or rejecting means 10.

The actuated pins are returned to normal or neutral position by a cam 305 formed as an integral part of the mounting bracket 268. which bracket is mounted on a mounting bracket 308 for the solenoid 212. The bracket 308 is in turn mounted upon the supporting bracket for the shaft I30. as best shown in Fig. 14. The bracket 268 is provided with an opening 3"] through which the cam lug 210 projects. and an edge of this opening limits the outward movement 01' the lever arm 260 under the action of a. spring {H2 secured between a pin carried by the bracket 258 and 9. lug 314 formed on the lever arm 260.

It i apparent from the foregoing description that as the pinwheel or drum 236 revolves, the

pins successively actuate the switch 283 to enerelse the switches of the end contour testing devices I I8 and I20. 11', at this energized instant, the feelers of these devices engage a can end of abnormal contour, the central feelers of these testing devices H3 and I20 will be flexed relative to the outer sets of feelers, as shown in Figs. 26 and 2'7, to complete a circuit, as previously described, to the solenoid 212 which also, as previously described, pre-sets one of the pins to a position projecting a greater than normal distance beyond the periphery of the drum 236. This pre-set pin moves, as will be evident, in exact synchronism with the tested can, and as the pinwheel or drum revolves it engages the lever mechanism 284 to actuate the switch 213 to control the actuating solenoids 302 and 304 and the can rejecting or directing means I0. As the pre-set pin passes beyond the switch operating lever mechanism 284 it is engaged by the cam surface 306, to be thereby returned to neutral position with respect to the wheel or drum 236. and it simultaneously engages the cam lug 210 to energize the contacts of the end contour testing devices H8 and I20, there being at this instant a can properly positioned between these testing devices.

As previously indicated, the operation of the pressure testing mechanism 3 is controlled by the control mechanism 4 to be rendered inoperative if no cans are available for testing, and to be rendered operative only when cans are available for testing. For this purpose the clutch mechanism I40, which operates to connect the driving pulley I38 to the shaft I30, is controlled by solenoid 3I5 energized by the switch 82, through a circuit subsequently to be described, the switch 82 being actuated. as previously described. by the balanced track 50.

The clutch mechanism I40 comprises a disk or plate 3I8 provided with a friction ring or annuhis 320 adapted to engage a face of the pulley I33, the plate 3I8 being carried by a grooved collar 322 splined on the shaft I30 for rotation therewith and for axial movement relative thereto to withdraw the friction ring 320 from contact with the pulley I38. The friction ring 320 is normally held in contact with the pulley by a coil spring 324 embracing the shaft I30 and interposed between the grooved collar 322 and a collar or abutment 326. The solenoid 3I5 actuates the collar 322 axially of the shaft against the force of the spring 324 to release the clutch mechanism through a lever 323 connected with the armature of the solenoid by a link 330, the lever 323 being provided at its upper end with a substantially U-shaped yoke 332 having inwardly projecting pins 334 engaging in the groove 336 in the collar 322. The lever 328 is pivoted at its upper end by means of a pin or pins 333 passing through openings in the arms in the U- shaped yoke 332 and carried by a mounting plate or plates 340 secured to one oi the plates I50, Fig. 14. Means are provided for stopping the clutch plate 3I8 and the shaft I30 when the clutch is operated by solenoid 3I8, and this means or brake comprises a plunger 342 slidably and adjustably mounted in a housing 344 carried at the upper end of one of the arms of the U- shaped yoke 332. The plunger 342 is resiliently urged into braking position by an embracing coil spring 346 interposed between the head of the plunger and the bottom of a receiving opening in the housing 344. It will be evident that when the solenoid 3I6 is energized, the clutch operatlug lever 328 will be moved in a clockwise direction. as seen in Fig. 14, about its pivot stud 333, thereby to move the clutch collar 322 axially of the shaft I30 away from the pulley I33, this collar in turn moving the clutch ring 320 out of engagement with the pulley and the clutch collar carrying the plate 3I8 into braking engagement with the braking plunger 342 which thereby brings the clutch plate and the shaft I30 quickly to rest.

The can directing or rejecting means I0 comprises a track 348 along which normal cans are directed to the viscosity or fluid friction testin mechanism I2, 2.. track or channel 350 alon which cans of abnormal contour are directed to a point of discharge or a suitable receptacle, and a pair of gates or control members 352 and 354 controlled by the solenoids 302 and 304 for selectively directing the cans to the tracks 348 and 350. Cans are delivered to the gates 352 and 354 from the star wheel H4 by means of a sharply inclined track 358, Fig. 11, on which the cans are moved by the star" wheel as it rotates, the track 356 being carried by one or both of the plates I50 of the pressure testing mechanism.

The gates 352 and 354 may comprise angle bars, each secured to the outer ends of the arms 358 of a bell crank, the other arm 380 of which is connected to the core of the actuating solenoids 302 and 304 by means of a link 332. The bell cranks 353 are pivoted by shafts 364 to brackets 366 carried by spaced supporting plates 33! also forming guide rails limiting the sidewise movement of the cans. The supporting and guiding plates 368 are fastened to an angle bar 3'50, in turn secured to the rails I02 of the inclined track 38. When the switch 216, Fig. 19, is actuated by the lever mechanism 204 in response to the presence of a defective can at the point of discharge of the pressure testing mechanism, the solenoids 302 and 304 are simultaneously energized to move the gates 352 and 354 outwardly to uncover the reject channel or track 350, the switch 216 being held closed by a pin 244 acting through the lever mechanism 234 until the defective can has rolled down the track 358 and into the reject channel 350. The actuating pin 244 then releases the lever mechanism 284 and the switch 218, energized and the gates 352 and 354 returned to normal closed position by the weight of the cores of the solenoids or by auxiliary springs, if desired. A can of normal end contour will not cause actuation of the switch 218 and, hence. such can, when discharged from the star" wheel II4 will roll along the track 356 onto the gate bars 352 and 354 and across to the track 348 by which such cans are fed to the viscosity or fluid friction testing mechanism I 2.

The jamming up of cans in the size testing mechanism 8 due to a stoppage of the pressure testing mechanism, will not, of course, damage the size testing mechanism, for the cans of normal length which are at the moment positioned between the plane surfaces 36 of the disks 04 (Figs. 8 and 10) will simply rest on the track rails 52 and I03 passing through these disks, and this line of cans will prevent the gravity feed of more cans to the disks 84.

Operation of the machine the solenoids 302 and 304 are decannot pass between the rotating disks ll of this size-testing mechanism and are, therefore, carried by the peripheral portion 9 of these disks upwardly and deposited on the inclined storage track 98. Cans of normal length roll freely between these disks 84 onto the rails I05, by which they are fed into the pressure-testing mechanism 8. Filled cans which are defective in respect to the abnormality of the pressure of their contents, or which are defective in other respects as evidenced by the abnormality of their end contours, are detected in this mechanism. Such defective cans are directed or fed into the rejecting channel 350 (Figure 11) through the can-directing or rejecting means I II, the operation of which is determined, as previously described, by the pressure-testing mechanism I. Cans of normal internal pressure and end contour freely roll or pass through the gates of the can-directing or rejecting means in and are fed along the gravity track 348 into the viscosity-testing mechanism it] Every filled can. passing into the viscositytesting mechanism I2, is first rotated in one direction and then fed onto the gravity track section along which the cans tend to rotate in a direction opposite to the previous direction of rotation of the can and opposite to the direction of rotation of the contents of the can. so that cans are projected from the end of the gravity track section at different speeds and diflerent trajectories in accordance with the viscosity of the can contents.

It will be evident, from the foregoing description that applicant has provided a method and apparatus for detecting bloated cans or cans having abnormal internal pressures. as evidenced by their end contours, and for rejecting or directing along one path the filled containers, the contents of which are of abnormal internal pressure and for directing along another path the containers the contents of which are of normal internal pressure. It will be further evident that the method and apparatus are particularly adapted for rapidly and efliciently testing a succession of small. filled containers. It will also be apparent that this method and apparatus will be adapted for use in conjunction with other methods and apparatus for testing containers for other defects. such as abnormal length, abnormal viscosity and abnormal weight.

Changes may be made in the form, construction and arrangement of the parts without departing from the spirit of the invention or sacridoing any of its advantages, and the right is hereby reserved to make all such changes as fairly fall within the scope of the following claims.

We claim:

1. A mechanism for detecting filled cans'having abnormal internal pressures. which comprises can-conveying means, switch-carrying means including relatively shiftable members adapted to engage an end of each can carried by said conveying means and to be deflected relatively different distances in accordance with the axial distances between predetermined radially spaced areas on end surfaces of the cans, means receiving cans from said conveying means for directing the cans selectively in different directions. electrically operable means operatively controlled by said switch-carrying means for controllin the can-receiving and directing means, and means for preventing control of said electrically operable means by said switch-carrying means except when the movable members of said switch-carrying means engage predetermined points on the end surface of the can.

2. A mechanism for detecting filled cans having abnormal internal pressures. which comprises can conveying means, separate switch-carrying means adapted to simultaneously engage the opposite ends of a can carried by said conveying means, each of said switch-carrying means including relatively shiftable members engaging the end of the can and adapted to be deflected relatively dlilerent distances in accordance with. the axial distances between predetermined radially spaced points on the end surfaces of the cans, means receiving cans from said conveying means for directing the cans selectively in different directions, an electrically operable means operatively controlled by either of said separate switch means for controlling said can receiving and directing means to control the same whereby cans either end of which is abnormal are directed by said receiving and directing means in a different direction than cans of normal pressure.

3. A mechanism for detecting filled cans having abnormal internal pressures. which comprises can conveying means. switch-carrying means including relatively movable members adapted to engage an end of each can carried by said conveying means at spaced apart areas on the end of the can and to be deflected relatively different distances in accordance with the axial distance between the points of engagement with the can end. means receiving cans from said conveying means for directing the cans selectively in different directions. electrically operable means controlled by said switch-carrying means for operatively controlling presettable means for operating the can directing means to cause the can directing means to direct cans oi abnormal internal pressures in a different direction than normal cans. and means for preventing control of said electrically operable means b said switchcarrying means except when the movable members of said switch-carrying means engage the end surface of a can at predetermined points.

4. A mechanism for detectin filled cans having abnormal internal pressures, which comprises can conveying means, separate switch-carrying means adapted to simultaneously engage the opposite ends of each can carried by said conveying means. each of said switch-carrying means including relatively movable members adapted to engage the end of the can at spaced apart areas on the end of the can and to be deflected relatively different distances in accordance with the axial d'stances between the points of engagement with the can ends, means receiving cans from said conveying means for directing the cans selectively in different directions. electrically operable means controlled by either of said switch-carrying means for operatlvely controlling presettable means for operating the can directing means to cause the can directing means to direct cans of abnormal internal pressures in a diflerent direction than normal cans. and means for preventing control of said electrically operable means by said switch-carrying means except when the movable members of said switch-carrying means engage the end surface of a can at predetermined points.

5. A mechanism for detecting filled cans having abnormal internal pressures. which comprises means for conveying cans continuously past a station, relatively movable members at said station adapted to engage an end of each can carried past said station at spaced apart areas on the end of the can and to be deflected by each can relatively different distances in accordance with the axial distances between the points of engagement with the can end, means receiving cans from said conveying means for directing the cans selectively in different directions, and means actuatable by said relatively movable surface engaging members when said surface engaging members engage the end of a can at predetermined points, said actuatable means being operatively connected to said can receiving and directing means to control the same whereby abnormal cans are directed by said receiving and directing means in a different direction than cans of normal pressures.

6. A mechanism for detecting filled cans having abnormal internal pressures. which comprises means for conveying cans continuously past a station. separate sets of relativel movable members at said station adapted to simultaneously engage the opposite ends of each can carried past said station. each set of members engaging the end of the can at spaced apart areas and each set being adapted to be deflected by each can relatively difierent distances in accordance with the axial distance between the points of engagement with the can end. means receiving cans from said conveying means for directing the cans selectively in different directions, and means actuatable by either of said relatively movable sets of members when said members engage each end of a can at predetermined points, said actuatable means being operatively connected to said can receiving and directing means to control the same whereby abnormal cans are directed b said receiving and directing means in a different direction than cans of normal pressures.

'7. A mechanism for detecting filled cans having abnormal internal pressures. which comprises means for conveying cans continuously past a station, switch-carrying means at said station including relatively movable members adapted to engage an end of each can carried past said station at spaced apart areas on the end of the can and to be deflected relativel different distances in accordance with the axial distance between the points of engagement with the can end. means receiving cans from said conveying means for directing the cans selectively in different directions, electrically operable means operatively controlled by said switch-carrying means for controlling the can receiving and directing means to cause the can directing mean to direct cans of abnormal internal pressures in a different direction than normal cans, and means for preventing control of said electrically operable means by said switch-carrying means except when the movable members of said switch-carrying means engage the end surface of a can at predetermined points.

8. .A mechanism for detectin filled cans having abnormal internal pressures. which comprises means for conveying cans continuously past a station, separate switch-carrying means at said station adapted to simultaneously engage the opposite ends of each can carried past said station, each of said switch-carrying mean including relatively movable members adapted to engage the end of the can at spaced apart areas and to be deflected relatively different distances in accordance with the axial distances between the points of engagement with the can ends, means receiving cans from said conveying means for directing the cans selectivel in diiferent directions, electricall operable means operatively controlled by either of said switch-carrying means for controlling the can receiving and di recting means. and means for preventing control of said electrically operable means by said switchcarrying means except when the movable members of said switch-carrying means engage the end surface of a can at predetermined points.

9. A mechanism for detecting filled cans having abnormal internal pressures. which comprises means for conveying cans continuously past a station. relatively shiftable members in said station adapted to engage an end of each can at spaced apart areas and to be deflected by each can relatively difierent distances in accordance with the axial distance between the points of engagement with the can end, means receiving cans from said conveying means for directing the cans selectively in difierent directions, means actuatable by said relatively movable members and operatively connected to said can receiving and directing means to direct abnormal cans in a different direction than normal cans, and means for preventing actuation of said actuatable means by said members except at spaced points on said conveying means at which the ends of cans carried thereby are engaged by said members at predetermined spaced apart points.

10. A mechanism for detecting filled cans having abnormal internal pressures, which comprises means for conveying cans continuously past a station. separate sets of relativel shiftable members in said station adapted to engage the opposite ends of a can simultaneously, each set of members including members engaging the ends of the can at spaced apart areas and adapted to be deflected relatively difierent distances in accordance with the axial distance between the points of engagement with the can ends, means receiving cans from said conveying means for directing the cans selectively in different directions. means actuatable by either of said sets of relatively movable members and operatively connected to said can receiving and directing means to cause the directing means to direct abnormal cans in a different direction than normal cans, and means for preventing actuation of said actuatable means by said members except when said members engage the end of a can at predetermined spaced apart points.

11. A mechanism for detecting filled cans having abnormal internal pressures which comprises can conveying means, switch-carrying means including three relatively shiftable members adapted to engage an end of each can carried by said conveying means and to be deflected relatively different distances in accordance with the axial distance between their points of engagement with the can end, two of said members at one stage contacting the rim of the can at spaced points and a third member contacting the can at a point on the end spaced inwardly from the rim, means receiving cans from said conveying means for directing the cans selectively in different directions, electrically operable means operatively controlled by said switch-carrying means for controlling said can receiving and directing means to cause the can directing means to direct cans of abnormal internal pressures in a diiferent direction than normal cans and means for preventing control of said electrically operable means by said switch-carrying means except at said one stage when the two movable members of said switch-carrying means engage the rim of the can at spaced points and the third engages the end of the can at a point spaced inwardly from the rim.

12. A mechanism for detecting filled cans having abnormal internal pressures, which comprises can conveying means, separate switch-carrying means adapted to simultaneously engage the opposite ends of each can carried by said conveying means, each of said switch-carrying means including three relatively shiftable members adapted to engage the end of the can and to be deflected relatively different distances in accordance with the axial distance between their points of engagement with the can end, two of said members in each set at one stage contacting the rim of the can at spaced points and the third mem.. her in each set contacting the can at a point on the end spaced inwardly from the rim, means receiving cans from said conveying means for directing the cans selectively in difierent directions, electrically operable means operatively controlled by either of said switch-carrying means for controlling said can receiving and directing means to cause the can directing means to direct cans of abnormal internal pressures in a different direction than normal cans, and means for preventing control of said electrically operable means by said switch-carrying means except when the two movable members of said switch-carrying means engage the rim of the can at spaced points and the third engages the end of the can at-a point spaced inwardly from the rim,

13. A method oi! handling filled cans which comprises feeding the cans along a given path, testing the cans for length and removing those of abnormal length, and testing the remaining cans moving along said path for internal pressure by determining the contour of both ends thereof simultaneously and removing those cans having abnormal internal pressures.

14. A machine for handling filled containers which comprises means for feeding the containers along a given path, means at a first station for testing the containers for length and for discharging those of abnorma1 length in one direction and those oi normal length in another direction, and means at a second station receiving the cans of normal length from said first testing means for testing the end contour of both ends of the received containers simultaneously to determine the internal pressures of their contents, and means operatively controlled by said lastmentioned testing means for separating the containers the contents of which are of abnormal internal pressures from containers the contents of which are of normal pressures.

15. A machine for handling filled containers, which comprises means for feeding the containers along a given path, means at a first station for testing the containers for length and for discharging those of abnormal length from said path and directing along aid path those of normal length, means at a second station receiving the cans of normal length from said first testing means for testing the end contour of the received containers to determine the internal pressure of their contents, said means at a second station comprising a pair of members contacting the rim of the can at spaced points and a third member contacting the end of the can at a point spaced inwardly from the rim, said members being relatively movable axially of the can, and means operatively controlled by said means at a second station for separating the containers the contents of which are of abnormal pressures from containers the content oi which are of normal pressures.

16. A machine for handling filled containers, which comprises means for feeding the containers along a given path, means at a firststation for testing the containers for length and for discharging those of abnormal length from said path and directing along said path those of normal length, mean at a second station receiving the cans of normal length from said first testing means for testing the end contour of both ends of the received containers simultaneously to determine the internal pressures of their contents, said means at a second station comprising separate sets of members for testing the end contour of the opposite ends of the containers, each of which sets of members comprises a pair of members contacting the rim of the can at spaced points and a third member contacting the end of the can at a point spaced inwardly from the rim, the members in each set being movable relative to each other axially of the can, and means operatively controlled by each of said sets of members for separating the containers the contents of which are of abnormal internal pressures from containers the contents of which are of normal pressures.

17. A mechanism for detecting filled cans having abnorma1 internal pressures, which comprises means for conveying cans continuously past a station, relatively movable members at said station mounted in position to be engaged at spaced points by an end surface of each can carried past said station and movable by each can relative to their mounting in a direction away from the can different distances in accordance with the distance between said points in a direction transverse to said end, and means actuated by at least one of said members on abnormal relative movement of said members with respect to one another for indicating a filled can of abnormal internal pressure.

18. A mechanism for detecting filled can having abnormal internal pressures, which comprises means for conveying cans continuously past a station, relatively movable members at said station mounted in position to be engaged at spaced points by an end of each can and movable by each can relative to their mounting in a direction away from the can relatively different distances in accordance with the distance between predetermined points on an end surface of the can in a direction axially of the can, and electrically operated means operably controlled by at least one of said members on abnormal relative movement oi said members with respect to one another for indicating a filled can of abnormal internal pressure.

19. A mechanism for detecting filled cans having abnormal internal pressures, which comprises means for conveying can continuously past a station, relatively movable members at said station mounted in position to be engaged at spaced points by an end surface of each can carried past said station and movable by each can relative to their mounting in a direction away from the can relatively different distances in accordance with the distance between said points in a direction transverse to said end, means receiving cans from said conveying means for directing the cans selectively in difierent irections and means actuatable by said relatively movable surface-engag- -ing members upon movement with respect to one another and operatively connected to said can receiving and directing means to control the same whereby abnormal cans are directed by said receiving and directing means in a different direction than cans of normal pressures.

20. A mechanism for detecting filled cans having abnormal pressures, which comprises means for conveying cans continuously past a station, relatively movable switch carrying mean at said station mounted in a position to be engaged at spaced points by an end surface of each can carried past that station and movable by each can relative to their mounting in a direction away from the can and axially thereof relatively different distances in accordance with the distance between said points, means receiving cans from said conveying means for directing the cans selectively in difierent directions, and electrically operable means operatively controlled by said switch carrying means for controlling said can receiving and directing means to control the same whereby abnormal cans are directed by said receiving and directing means in a different direction than cans of normal pressure.

21. A mechanism for detecting filled cans having abnormal internal pressures, which comprises means for conveying cans continuously past a station, separate sets of relatively movable members at said station mounted in a position to be engagcd at spaced points by opposite end surfaces of each can carried past said station and movable by each can relative to their mountings in directions away from the can different distances in accordance with the distances between said points in directions transverse to said ends, and means actuated by said members on abnormal relative movement of the members in either set with respect to one another for indicating a filled can of abnormal internal pressure.

ROY O. HENSZEY.

PAUL SMART.

Certificate of Correction Patent No. 2,400,507.

May 21, 1946.

ROY O. HENSZEY ET AL.

It is hereby certified that errors appear in the printed specification of the above numbered patent requiring correction as follows: Page 1, first column, line 2, for

apapratus read apparatus; page 2, first column, line 5, for 11 and 20 read 11 to 20' line 22, strike out various before testing; line 45, for finger read finer; first column, line 46, for budged read bulged; and that the said Letters lie atent should be read with these corrections therein that the same may conform to the record of the case in the Patent Oihce.

Signed and sealed this 25th day of February, A. D. 1947.

LESLIE FRAZER,

First Assistant C'ommissioner of Patents.

whereby abnormal cans are directed by said receiving and directing means in a different direction than cans of normal pressures.

20. A mechanism for detecting filled cans having abnormal pressures, which comprises means for conveying cans continuously past a station, relatively movable switch carrying mean at said station mounted in a position to be engaged at spaced points by an end surface of each can carried past that station and movable by each can relative to their mounting in a direction away from the can and axially thereof relatively different distances in accordance with the distance between said points, means receiving cans from said conveying means for directing the cans selectively in difierent directions, and electrically operable means operatively controlled by said switch carrying means for controlling said can receiving and directing means to control the same whereby abnormal cans are directed by said receiving and directing means in a different direction than cans of normal pressure.

21. A mechanism for detecting filled cans having abnormal internal pressures, which comprises means for conveying cans continuously past a station, separate sets of relatively movable members at said station mounted in a position to be engagcd at spaced points by opposite end surfaces of each can carried past said station and movable by each can relative to their mountings in directions away from the can different distances in accordance with the distances between said points in directions transverse to said ends, and means actuated by said members on abnormal relative movement of the members in either set with respect to one another for indicating a filled can of abnormal internal pressure.

ROY O. HENSZEY.

PAUL SMART.

Certificate of Correction Patent No. 2,400,507.

May 21, 1946.

ROY O. HENSZEY ET AL.

It is hereby certified that errors appear in the printed specification of the above numbered patent requiring correction as follows: Page 1, first column, line 2, for

apapratus read apparatus; page 2, first column, line 5, for 11 and 20 read 11 to 20' line 22, strike out various before testing; line 45, for finger read finer; first column, line 46, for budged read bulged; and that the said Letters lie atent should be read with these corrections therein that the same may conform to the record of the case in the Patent Oihce.

Signed and sealed this 25th day of February, A. D. 1947.

LESLIE FRAZER,

First Assistant C'ommissioner of Patents. 

